maternofetal transmission of human parvovirus b19 genotype 3 in ghana, west africa
DESCRIPTION
Maternofetal transmission of human parvovirus B19 genotype 3 in Ghana, West Africa. D Candotti, K Danso, A Parsyan, A Dompreh, J-P Allain. National Blood Service, England Div. Transfusion Medicine, University of Cambridge, UK - PowerPoint PPT PresentationTRANSCRIPT
Maternofetal transmission of human parvovirus B19 genotype 3
in Ghana, West Africa
D Candotti, K Danso, A Parsyan, A Dompreh, J-P Allain
National Blood Service, England
Div. Transfusion Medicine, University of Cambridge, UK
Dept. Obstetrics & Gynaecology and Dept. Microbiology, Komfo Anokye
Teaching Hospital, Kumasi, Ghana
B19 infection in Ghana
• 82% seroprevalence in adults
• B19 DNA prevalence:- 1.3% in blood donors- 11.5% in children (average age: 23 months)
• 0.9% persistent infections:- IgG only- low viral load ( 102- 105 IU/ml)
• Endemic region for B19 genotype 3
Phylogenetic tree of full length human parvovirus B19 genomes
0.005 substitutions/site
Genotype 2
Genotype 1
Genotype 3
3A
3B
100
100
100
100
100V9
D91.1
Study design
Pregnant women plasmas(n=885)
B19 DNA screeningMultiplex QPCR assay
Single QPCR & nested PCR confirmation
Specific QPCR & nested PCR
Cord blood plasmasNewborn whole blood
Anti-VP2 IgG
SequencingGenotyping
Serological and viral markers in pregnant women
Anti-VP2 IgG reactive 144/177 (81%)
Confirmed DNA pos. 16/885(1.8%)
DNA load (IU/ml) Median Range
1.3E+0346 - 3.6E+06
IgM reactiveIgG reactive
3/1616/16
Maternofetal transmission
19642005
16551956177419412246202921061818219614472409224221431577
Mother Cord blood Newborn
Viral load(IU/ml)
IgMtiter
IgGtiter
Viral load(IU/ml)
IgMtiter
Viral load(IU/ml)
SampleID
Type
1.1E+041.2E+06
3.6E+065.9E+034.2E+032.1E+031.5E+031.3E+031.2E+031.1E+036.5E+025.6E+023.3E+025.8E+014.6E+014.6E+01
1:10001:1000
1:100<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10
1:10001:1000
1:1000001:10000
1:10001:10000
1:1001:10001:10001:100
1:10001:10001:10001:10001:1001:100
1.1E+032.1E+06
00000000000000
<1:101:1000
<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10<1:10
1.7E+03-
0-------0-0---
33
33333133333333
Conclusions
• B19 genotype 3 is dominant in Ghana and is characterised by high genetic variability
• 2/3 cases of primary maternal B19 infection resulted in vertical transmission
• No evidence that maternal persistent B19 is vertically infectious
Acknowledgements
Pr J.-P. AllainDr A. Parsyan
Div. of Transfusion MedicineUniversity of Cambridge
Cambridge, UK
Dr K. DansoDept. of Obstetrics & GynaecologyKomfo Anokye Teaching Hospital
Kumasi, Ghana
Mr A. DomprehSerology laboratory
Dept. of MicrobiologyKomfo Anokye Teaching Hospital
Kumasi, Ghana
Mr C HornPlasmacute
Norway
National Blood ServiceEngland